The present invention relates to a lower vehicle-body structure of a vehicle which can improve the performance against an offset frontal collision of the vehicle, and, in particular, relates to a lower vehicle-body structure of a vehicle comprising a dash panel which extends in a vehicle width direction, a hinge pillar which is connected to an end portion, in the vehicle width direction, of the dash panel, a side sill which is connected to a lower portion of the hinge pillar and extends in a vehicle longitudinal direction, and a floor panel which is connected to the side sill.
In general, in an offset frontal collision of a vehicle, particularly, in a small overlap collision (in an offset collision on the outside, in a vehicle width direction, of a pair of right-and-left front side frames), vehicle's tires retreat, so that a hinge pillar as well as a side sill deform. Accordingly, some countermeasures for the small overlap collision has been desired. Japanese Patent Laid-Open Publication No. 2005-193843, Japanese Patent Laid-Open Publication No. H7-89450, and Japanese Patent Laid-Open Publication No. 2007-203893 disclose conventional structures to improve the collision performance.
The one of the conventional structures disclosed in the above-described first patent publication is such that a dash cross member which extends in the vehicle width direction is provided at a vehicle-inside lower portion of the dash panel, and a gusset member which connects the dash cross member to a hinge pillar and a side sill is provided, so that the hinge pillar can be prevented from falling inward in a side collision of a vehicle, thereby improving the performance against the vehicle's side collision.
The one of the conventional structures disclosed in the above-described second patent publication is such that a connection portion between a hinge pillar extending vertically and a side sill extending longitudinally is reinforced by a reinforcing member which is formed in an L shape in a side view, so that the connection portion can be prevented from deforming in a frontal collision of a vehicle, thereby improving the performance of the vehicle's frontal collision.
The one of the conventional structures disclosed in the above-described third patent publication is such that in a side sill having a closed cross section extending in the vehicle longitudinal direction, a front reinforcement which has a L-shaped cross section and extends longitudinally is provided between a lower portion of a hinge pillar and a lower portion of a center pillar, and a rear reinforcement is arranged such that its front portion overlaps the front reinforcement and the rear reinforcement is directed further rearward from the lower portion of the center pillar, so that the side sill can be prevented from bending in an offset frontal collision of a vehicle, thereby improving the performance of the vehicle's offset frontal collision.
However, none of the above-described first, second and third patent publications discloses or teaches any structure to restrain an overall cabin deformation on the side of a vehicle's side portion in the offset frontal collision of a vehicle (particularly, in the small overlap collision).